Metadata Service

Applies To: Microsoft Dynamics AX 2012 R2, Microsoft Dynamics AX 2012 Feature Pack, Microsoft Dynamics AX 2012

The metadata service returns information about AOT objects in Microsoft Dynamics AX such as tables, services, extended data types (EDTs), enums, and so on. The metadata service is:

• automatically installed

• by default, hosted by the Application Object Server (AOS)

• always available

• a Windows Communication Foundation (WCF) service that adheres to WCF protocols and standards

How the Metadata Service Works

The metadata service has two types of service operations:

• Service operations that return names or keys – these service operations return the names or keys for all queries, tables, menus, and so on. The names are returned in a string array. The name of the metadata service operation specifies the names that are returned. For example, the GetQueryNames method returns a string array of names for all the queries in the installation.

• Service operations that return metadata – these service operations take a string array of names, an integer array of IDs, or an array of key objects (such as MenuItemKeys[ ]) and return the metadata for those objects. Each of these service operations returns an array of metadata objects.

  For example, the signature of the service operation to retrieve query metadata is: QueryMetadata[] GetQueryMetadataByName(string[] queryNames). The QueryMetadata objects that are returned in the QueryMetadata[] array derive from the QueryMetadata class.

To use the metadata service, you call the service operation to retrieve the object names. Then, you call the metadata service operation and pass in the name or names to retrieve the metadata for those objects as shown in the following code:

    static void Main(string[] args)
        {
            AxMetadataServiceClient client = new AxMetadataServiceClient();

            try
            {

                 // Gets the names of all services in a string array.
                string[] services = client.GetServiceNames();

                // Loops through all the service names and prints them to the console.
                foreach (string serviceName in services)
                {
                    Console.WriteLine("Service named: {0}", serviceName);
                }

                // Gets the name of the first service.
                string[] serviceNames = new string[1];
                serviceNames[0] = services[0];


                // Gets the metadata for the first service.
                ServiceMetadata[] serviceMetadata = client.GetServiceMetadataByName(serviceNames);


                client.Close();
            }
            catch
            {
                client.Abort();
                throw;
            }

        }

For more information about calling the metadata service, see Walkthrough: Calling the Metadata Service.

The following table lists the metadata service operations that return object names or keys.

The following table lists the metadata service operations that return object metadata.

These service operations return an array of metadata objects. The metadata object contains the actual metadata. The type of metadata object returned depends on the service operation. For example, the GetQueryMetadataByName service operation returns an array of QueryMetadata objects. The QueryMetadata object contains the metadata for a single query and this metadata is exposed through the object methods and properties. For example, the QueryMetadata object has properties such as Name, QueryType, DataSources, and AllowCrossCompany.

The metadata classes reside in the Microsoft.Dynamics.AX.Framework.Services.Metadata.Contracts namespace. Some commonly used top-level metadata classes include the following:

• DimensionMetadata

• EnumMetadata

• FieldMetadata

• FormControlMetadata

• LabelMetadata

• ListPageMetadata

• MenuMetadata

• MenuItemMetadata

• QueryMetadata

• ServiceMetadata

• ServiceGroupMetadata

• TableMetadata

Metadata Service Architecture

The metadata service is a WCF service that is contained in the Microsoft.Dynamics.AX.Services.Metadata.Service.dll assembly. This assembly is located in the server Bin directory. Depending on your configuration, the assembly is located in a directory such as C:\Program Files\Microsoft Dynamics AX\<version>\Server\MicrosoftDynamicsAX\Bin.

The metadata service has the following configuration default values:

• It is hosted by the AOS on port 8201 and the URL is net.tcp://servername:8201/DynamicsAx/Services/MetadataService.

• The service WSDL URL is http://servername:8101/DynamicsAx/Services/MetadataService

• It uses the netTcpBinding binding.

These settings will vary depending on what port number the service port and the WSDL port have been configured to use.

The configuration settings for the metadata service are found in the Ax32Serv.config file which is also located in the server Bin directory.

Metadata Service Security

Only authenticated Microsoft Dynamics AX users can access the metadata service. In order to retrieve data by using the metadata service, you must have a valid username in Microsoft Dynamics AX. The metadata service uses Windows integrated security. Therefore, when a caller invokes the metadata service, the system verifies the credentials under which the calling client is running and verifies that the username is a valid Microsoft Dynamics AX user.

The metadata service is available to all authenticated users. Therefore, all security roles have the same access level to metadata information.

See also

AIF System Services

Metadata Service Class Diagrams

Walkthrough: Calling the Metadata Service

Walkthrough: Using the Metadata Service to Get Table Field Labels